Use a dedicated type for the opaque type parameter to WorkQueue in layout.
Currently, we use UnsafeFlow and UnsafeLayoutNode, both of which are aliases
for (usize, usize) and thus interconvertible. This change should make it
clearer that the WorkQueue is not limited to one particular type.
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Currently, we use UnsafeFlow and UnsafeLayoutNode, both of which are aliases
for (usize, usize) and thus interconvertible. This change should make it
clearer that the WorkQueue is not limited to one particular type.
those instead of working on nodes one-by-one.
This reduces the overhead of the work-stealing traversal function
significantly. It's especially important on ARM, where memory barriers are
expensive.
A rebuild after touching components/profile/mem.rs now takes 48 seconds (and
only rebuilds `profile` and `servo`) which is much lower than it used to be.
In comparison, a rebuild after touching components/profile_traits/mem.rs takes
294 seconds and rebuilds many more crates.
This change also removes some unnecessary crate dependencies in `net` and
`net_traits`.
- Most of util::memory has been moved into profile::mem, though the
`SizeOf` trait and related things remain in util::memory. The
`SystemMemoryReporter` code is now in a submodule
profile::mem::system_reporter.
- util::time has been moved entirely into profile::time.
This makes these parameters self-documenting.
This patch does not attempt to push those enums into the data
structures that feed calls to this function.
Fixes#4158.
Now that DOM/Flow traversals have been refactored out, the `recalc_style_for_subtree`
function in `css/matching.rs` can be removed, in lieu of just running the standard
`recalc_style_for_node` and `construct_flows` traversals sequentially. Now we
no longer have the maintenance headache of duplicating selector matching logic
in two places! \o/
r? @pcwalton
a separate `ClipDisplayItem`.
We push down clipping areas during absolute position calculation. This
makes display items into a flat list, improving cache locality. It
dramatically simplifies the code all around.
Because we need to push down clip rects even for absolutely-positioned
children of non-absolutely-positioned flows, this patch alters the
parallel traversal to compute absolute positions for
absolutely-positioned children at the same time it computes absolute
positions for other children. This doesn't seem to break anything either
in theory (since the overall order remains correct) or in practice. It
simplifies the parallel traversal code quite a bit.
See the relevant Gecko bug:
https://bugzilla.mozilla.org/show_bug.cgi?id=615734
stretching.
This preserves the usage of the Bloom filter throughout style recalc,
but the implementation is rewritten. Provides a 15% improvement on
Guardians of the Galaxy.
